DISPOSITIVO DI BLOCCAGGIO A DISIMPEGNO RITARDATO, PARTICOLARMENTE PER SPORTELLI DI MACCHINE LAVATRICI OSIMILI, COMPRENDENTE UNA PASTICCA PTC ED UN ELEMENTO BIMETALLICO

摘要

Delayed release locking control device, particularly for doors of washing machines and the like, containing inside a case a self-regulating resistive wafer heater of a material having a positive temperature coefficient (PTC) of resistance, a snap-acting bimetallic element connected to a latch or locking member, and terminals which carry electrical current to the PTC wafer heater, wherein the bimetallic element is arranged so means transform the linear snap like movement of an end of the bimetallic element into a rotary movement of the latch mounted on the case to cause it to rotate 90 DEG from a resting position into an operating position when the bimetallic element, selectively heated by the said PTC wafer, abruptly reverses its curvature upon reaching the actuating temperature of reversal and to cause the said latch to return to the resting position when the bimetallic element cools down again to below a reset temperature of reversal and snaps back to its normal curvature.